Liquid Fuel for Electric Cars

BETTER BATTERIES are the key to electric cars that can drive for hundreds of miles between rechargings, but progress on existing technology is annoyingly incremental, and breakthroughs are a distant prospect. A new way of organizing the guts of modern batteries, however, has the potential to double the amount of energy such batteries can store.

The idea came to Massachusetts Institute of Technology professor Yet-Ming Chiang while he was on sabbatical at A123 Systems, the battery company he co-founded in 2001. What if there was a way to combine the best characteristics of so-called flow batteries, which push fluid electrolytes through the cell, with the energy density of today's best lithium-ion batteries, the kind already in our consumer electronics?